Modern automobiles are, as is well known, equipped with a number of resources that assist the driver in controlling the vehicle and in monitoring the operability of the vehicle's various resources.
Typical of such resources are the vehicle's external light systems, brakes, windshield wipers, turn signals, back-up lights, brake lights, and engine status and warning signals, such as oil pressure, electric supply system, and so forth.
In operation of a vehicle, oftentimes signals are generated to warn the driver of impending trouble conditions which may or may not represent actual problems, but require interpretation and knowledge of other system conditions, before they can be properly interpreted and evaluated. As an example, most automobiles have some form of indication to inform the driver of low engine oil pressure. Low engine oil pressure, however, is not always an indication of an impending problem. For example, in case the engine is stalled while ignition is on, the oil pressure indication will come in, but since the engine is not running, absence of oil pressure is a perfectly normal condition. If announced simply as an oil pressure failure it will tend to unduly disturb a driver. A low oil pressure announcement should therefore be conditioned by an indication of whether the engine is running or not. As other examples of a vehicle resource linked to another resource is the windshield wipers which the driver will instinctively turn on in case vision is obscured by rain. In many states, however, it is also required that the headlights are turned on when the windshield wipers are running, or at least it is prudent of a driver to do so. Therefore. whenever a driver turns on the windshield wipers, it would be useful that a message, conditioned on presence of daylight, that the headlights should be turned on. As another example, many modern cars have two independent driving brake systems, and an indication of potential danger, if one of these brake systems is inoperative. This condition is, however, normally only indicated during short periods of time, for example after ignition is turned on, but before the engine is actually started. If one of the dual brake systems should fail, the brief indication may not be noticed by the driver, who may continue to drive with only partially operative brakes. It would therefore be better that the absence of a brake-in-order signal be combined with a lock-in signal, so that a faulty brake system would be announced in a locked-in condition that could be brought to the driver's attention before starting to drive.
Still other vehicle resources conditions may be combined to be interpreted and evaluated by suitable means and announced to the driver as will be described in more detail hereinbelow.
It is accordingly a primary object of the instant invention to provide a centralized resource management system for motor vehicles that overcomes the problem of adjusting the vehicle's resource status signals to a form that is readily evaluated and understood by the driver.